Hamayun Zafar | Umeå University (original) (raw)
Papers by Hamayun Zafar
African Vision and Eye Health, 2022
Background: Repeatability and validity are important components of precision in any measurement s... more Background: Repeatability and validity are important components of precision in any measurement system.Aim: This study aimed to determine the effect of change in head and neck position and body posture on the repeatability of intraocular pressure (IOP) measurements with PT-100 non-contact tonometer and compare with Goldmann, PT-100 and Schiøtz tonometer readings.Setting: Optometry clinic, Saudi Arabia.Methods: The IOP was measured in one selected eye of 84 healthy participants (mean aged 21.9 ± 2.0 years) using PT-100 in three head and body positions, Goldmann tonometer and Schiøtz on two separate visits, in a randomised fashion. Central corneal thickness (CCT) was measured using an ultrasound pachymeter. The repeatability, agreement and correlations between CCT and IOP differentials were assessed.Results: The IOP measured in three head and body positions with the PT-100 were similar and comparable to Goldmann IOPs in sessions one and two with 74% and 86% of PT-100 measurements with...
International Journal of Occupational Medicine and Environmental Health, 2022
Journal of Musculoskeletal & Neuronal Interactions, 2018
Objective: The present study aimed to compare the effects of quadriceps or calf muscles fatigue o... more Objective: The present study aimed to compare the effects of quadriceps or calf muscles fatigue on static and dynamic standing balance in young healthy adult males. Methods: Forty-five healthy, physically active male adults aged 18-30 years were randomly divided into three groups; Quadriceps muscle fatigue group (n=15), Calf muscles fatigue group (n=15), and a control group (n=15). The Modified Clinical Test of Sensory Interaction on Balance, Unilateral Stance, and Limits of Stability (reaction time and movement velocity) were selected as outcome measures for this study. Results: The results showed a non-significant difference between pretest and posttest balance scores (p>0.05) for quadriceps and calf muscles fatigue on balance. Similarly, there were non-significant differences in posttest balance scores when comparing fatigue effects between the groups (p>0.05). Conclusions: These results suggested that the fatigue of the quadriceps or calf muscles did not influence standing...
Journal of Musculoskeletal & Neuronal Interactions, 2018
Objective: The present study aimed to evaluate the effect of footwear on standing balance in heal... more Objective: The present study aimed to evaluate the effect of footwear on standing balance in healthy young adult males. Methods: Thirty healthy male participants aged 20-30 years were tested for standing balance on the Balance Master on three occasions, including wearing a sandal, standard shoe, or no footwear (barefoot). The tests of postural stability include; “Modified Clinical Test of Sensory Interaction on Balance” (mCTSIB), “Unilateral Stance” (US), and the “Limits of Stability” (LOS). The balance scores (mCTSIB, US, and LOS) was analyzed. Results: There was a significant effect between footwear conditions for mCTIB with eye closed on a firm surface (p=0.002). There was a significant effect between footwear conditions for the US with eye open and closed (p<0.05). There was a significant effect between footwear conditions for LOS reaction time during forward movement (p=0.02). Similarly, there was a significant effect between footwear conditions for LOS reaction time during ...
Investigative Ophthalmology & Visual Science, 2019
Purpose: Intraocular pressure (IOP) is important in the diagnosis and management of glaucoma and ... more Purpose: Intraocular pressure (IOP) is important in the diagnosis and management of glaucoma and remains the most significant, and only modifiable, risk factor for the development and/or progressio ...
Motor Control, 2021
The current study was carried out with the aim of investigating the effect of maximally relaxed l... more The current study was carried out with the aim of investigating the effect of maximally relaxed lying posture on disfluencies in young adults who stutter. A total of 24 participants (17 males, seven females; mean age = 24.9 ± 6.2 years) with developmental stuttering were a part of the study. The participants were asked to perform spontaneous speaking and reading aloud tasks in standard sitting and maximally relaxed lying postures. The severity of stuttering for the studied postures was estimated by using the Stuttering Severity Instrument. The results on the Stuttering Severity Instrument showed that stuttering parameters improved during the maximally relaxed lying posture compared with the standard sitting position. The results are discussed in the light of motor control concepts. It is concluded that the maximally relaxed lying posture can facilitate improvement in stuttering scores during spontaneous speaking as well as reading aloud in young adults who stutter. Reduced stutterin...
International Journal of Environmental Research and Public Health, 2020
Supermarket cashiers face a significant amount of stress, including time constraints, mental pres... more Supermarket cashiers face a significant amount of stress, including time constraints, mental pressure, and physical demands that require repetitive movements. The job description of a supermarket cashier involves work-related risk factors that may lead to musculoskeletal disorder (MSD) symptoms. This study aimed to investigate supermarket cashiers to determine the prevalence of MSD symptoms and their quality of life. Data were collected from a convenience sample of supermarket cashiers working in Saudi Arabia. Information included direct questions on pain in the previous 12 months, demographic data, and health- or occupation-related factors. Moreover, data was collected based on the 36-item short form survey (SF-36), and descriptive statistics were computed. A total of 193 supermarket cashiers participated in this study. The sample included 140 men (72.5%) and 53 women (27.5%), with a mean age of 27.2 ± 6.4 years. The majority of the participants (90%) had MSD symptoms in at least o...
BioMed Research International, 2018
Objective. The present study compared the effects of upright and slouched sitting postures on the... more Objective. The present study compared the effects of upright and slouched sitting postures on the respiratory muscle strength in healthy young males.Methods. A total of 35 adult male subjects aged 18–35 years participated in this study. Respiratory muscle strength was determined by measurement of sniff nasal inspiratory pressure (SNIP) using a MicroRPM device in the upright and slouched sitting positions. The subjects were asked to perform the pulmonary function test including peak expiratory flow (PEF), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio at baseline. Body composition was also determined.Results. There was a significant difference of SNIP score between upright sitting and slouched sitting positions (p=0.04). The mean difference of SNIP score between upright sitting and slouched sitting positions was 8.7 cmH2O. Significant correlations were found between SNIP in upright sitting and FEV1% predicted values [R= .651], SNIP in s...
Brain and Behavior, 2019
BackgroundJaw sensory‐motor system has been shown to affect static balance of the body. It would ... more BackgroundJaw sensory‐motor system has been shown to affect static balance of the body. It would be interesting to know whether it can influence dynamic balance as well. The objective of this study is to examine the influence of different jaw positions on dynamic balance using the Y‐balance test.MethodsEighty healthy male participants aged 20–35 years were invited to participate in this study. Dynamic balance was measured by the Y‐balance test in three directions (anterior, posteromedial, and posterolateral) for each leg separately in three jaw positions: resting jaw (control), open‐jaw, and clenched jaw.ResultsThere were no significant differences in reach distances between the different jaw positions except in the posterolateral direction. In comparison with resting jaw position, reach distance was significantly higher in open‐jaw position for the right leg and in clenched and open‐jaw positions for the left leg in the posterolateral direction.ConclusionsAlthough various studies h...
BioMed Research International, 2018
Background.Assessment of hand grip strength is vital for the evaluation of upper limb impairments... more Background.Assessment of hand grip strength is vital for the evaluation of upper limb impairments and effective exercise prescription. Present study primarily aimed to investigate the effect of head-neck positions on the hand grip strength in healthy young adults. Secondarily, the present study compared hand grip strength between left versus right hand in different head-neck positions.Methods.Healthy young adults (age 19 – 30 year; n = 40) participated in this cross-sectional study. Hand grip strength was assessed in three head-neck positions (neutral, rotation left, and rotation right) using the standard adjustable Jamar hand dynamometer.Results. Hand grip strength in both sides (left and right) was greatest in the head-neck neutral position. Hand grip strength measured in head-neck left rotation position displayed the least strength in both sides. There was no significant difference noted between left and right side hand grip strength measured in head-neck neutral and right rotati...
BioMed Research International, 2019
Objective. The current study aimed to investigate the effects of body position on the level and s... more Objective. The current study aimed to investigate the effects of body position on the level and severity of stuttering in young adults with developmental stuttering. Methods. A total of 24 subjects (male: 17; female: 7; mean age: 24.9 ± 6.2 years) with developmental stuttering participated. The participants were asked to perform oral reading and spontaneous monologue-speaking tasks in different body postures while their speech was recorded. During reading and speaking tasks, the Stuttering Severity Instrument was used to quantify the severity of stuttering. The effects of different body postures on stuttering severity, reading task, and speaking task scores were analyzed. Results. Significant differences in stuttering severity, reading task, and speaking task scores were found for different body postures. Post hoc analyses revealed a significant difference in stuttering severity, reading task, and speaking task scores when subjects were sitting on a chair with no arm support compare...
The Journal of Sports Medicine and Physical Fitness, 2019
BACKGROUND People clench their teeth to activate facial, neck and abdominal muscles when they nee... more BACKGROUND People clench their teeth to activate facial, neck and abdominal muscles when they need to generate heavy muscle force against large resistance like lifting heavy objects, in order to gain possible ergogenic advantage. These are termed as remote voluntary contractions. Aim of this study was to evaluate the effect of voluntary teeth clenching on maximal voluntary contraction of extensors and flexors of the knee, shoulder and elbow joints of the dominant side during slouch and unsupported upright sitting. METHODS One hundred healthy young male adults (mean age 23.3 years) participated in this study. Maximal voluntary contraction was measured using a hand-held dynamometer. RESULTS Jaw clenching caused different ergogenic effect during slouch versus unsupported sitting postures. The data revealed that during unsupported upright sitting, the effect of jaw clenching consistently results in larger maximal voluntary contraction of both extensor and flexor muscles of all the three studied joints. However, during slouch sitting, only the maximal voluntary contraction of extensors of elbow and flexors of knee were larger with clenched teeth position. CONCLUSIONS Jaw clenching can affect the maximal voluntary contraction of limb muscles which is sitting posture dependent. Jaw clenching can consistently facilitate certain muscles of the upper and lower limbs to generate greater force production during upright sitting.
Archives of Oral Biology, 2019
Journal of hand therapy : official journal of the American Society of Hand Therapists, Jan 23, 2017
Cross-sectional and clinical measurement. Assessment of hand function considers an essential part... more Cross-sectional and clinical measurement. Assessment of hand function considers an essential part in clinical practice. To develop normative values of hand grip strength and dexterity function for 6-12-year-old children in Saudi Arabia. Grip strength and dexterity function was measured in 525 children using Grip Track hand dynamometer (JTECH Medical, Midvale, UT, USA) and 9-hole pegboard test respectively. The grip strength and dexterity function was improved as age progressed regardless of gender. Across all age groups, the hand grip strength of boys was significantly higher than girls for dominant hand (31.75 ± 10.33 vs 28.24 ± 9.35; P < .001) and nondominant hand (31.01 ± 10.27 vs 27.27 ± 9.30; P < .001). The girls performed slightly faster than boys for dominant hand (19.70 vs 20.68; P < .05) and nondominant hand (21.79 vs 23.46; P < .05). In general, girls completed a 9-HPT faster than boys in the 2 of 7 age groups: 11 years (9-HPT scores = 2.10 seconds; P < .01)...
Workplace Health & Safety, 2017
Low back pain (LBP) is a common health problem. Professions like physical therapy (PT), involving... more Low back pain (LBP) is a common health problem. Professions like physical therapy (PT), involving frequent lifting, bending, or standing, are at risk for developing LBP. The objective of this study was to determine the prevalence of work-related LBP and factors associated with and consequences of work-related LBP among physical therapists in Riyadh, Saudi Arabia. A self-administered online questionnaire (i.e., demographic data, history of LBP before and after working as a physical therapist, work setting, and effect on daily activities) was sent to 600 members of the Saudi PT association. Data were analyzed using the Pearson chi-square test and Mann-Whitney U test. Eighty-eight percent of potential respondents completed the questionnaire. Of these, 89.65% of the therapists reported LBP after beginning their PT practice, and 35.6% reported LBP at the time of this survey. Gender, PT specialty, and duration of contact with patients were all found to be related to LBP. The prevalence of...
Somatosensory & Motor Research, 2016
Information about head orientation, position, and movement with respect to the trunk relies on th... more Information about head orientation, position, and movement with respect to the trunk relies on the visual, vestibular, extensive muscular, and articular proprioceptive system of the neck. Various factors can affect proprioception since it is the function of afferent integration, and tuning of muscular and articular receptors. Pain, muscle fatigue, and joint position have been shown to affect proprioceptive capacity. Thus, it can be speculated that changes in body posture can alter the neck proprioception. This study was undertaken to investigate the effect of body posture on cervicocephalic kinesthetic sense in healthy subjects. Cervicocephalic kinesthetic sensibility was measured by the kinesthetic sensibility test in healthy young adults while in (a) habitual slouched sitting position with arms hanging by the side (SS), (b) habitual slouched sitting position with arms unloaded (supported) (SS-AS), and (c) upright sitting position with arms hanging by the side (US) during maximum and 30 degree right, left rotations, flexion, and extension. Thirty healthy male adults (mean age 27.83; SD 3.41) volunteered for this study. The least mean error was found for the SS-AS position (0.48; SD 0.24), followed by SS (0.60; SD 0.43) and US (0.96; SD 0.71), respectively. For all test conditions, there was significant difference in mean absolute error while head repositioning from maximum and 30 degree rotation during SS and SS-AS positions (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). In conclusion, body posture can affect the proprioception function of the neck. Supporting the upper extremities in such a way that their weight is unloaded, which leads to reduction in the tension between the neck and shoulder girdle, can improve cervicocephalic kinesthetic sense in both the horizontal and vertical planes. The findings of this study can be implemented in people who have to do repeated arm and neck movements, by using ergonomically effective chairs with proper arm supports. This might help in prevention and treatment of neck pain.
BioMed Research International, 2018
Normal respiration is a very intricate function that comprises mechanical as well as nonmechanica... more Normal respiration is a very intricate function that comprises mechanical as well as nonmechanical components. It is shown to be affected by various factors including age, lifestyle, disease, and change in posture. With the increased use of hand held devices, everyone is prone to poor sitting postures like forward head posture. The purpose of this study was to evaluate the effect of assumed forward head posture and torticollis on the diaphragm muscle strength. A sample of 15 healthy males, aged 18-35 years, was recruited for this study. All subjects performed spirometry to measure the forced expiratory volume in 1 second (FEV1), the forced vital capacity (FVC), and FEV1/FVC ratio. SNIP was measured during upright sitting, induced forward head posture, and torticollis. Subject’s mean age (SD) was 23(6) years. The SNIP score of the subjects during sitting with FHP was lower as compared to that during upright sitting. It decreased significantly during induced right torticollis position...
BioMed Research International
Purpose. Cervical radiculopathy is disorder of cervical spinal nerve root affecting large number ... more Purpose. Cervical radiculopathy is disorder of cervical spinal nerve root affecting large number of population. Previously many studies are conducted to design suitable protocol for management of this disorder, but they lack in quality. The purpose of this study was to compare the effects of neural mobilization and cervical isometrics on health-related quality of life and deep flexors endurance in cervical radiculopathy. Methods. A double-blinded randomized clinical trial was conducted at Mayo Hospital, Lahore, Pakistan. Eighty-eight patients within the age range of 35-50 years were included in the study after taking their consent. In the experimental group ( n = 44 ), median nerve mobilization was applied along with cervical isometric exercises. The control group ( n = 44 ) performed cervical isometric exercises alone. Muscle endurance was measured by craniocervical flexion test and quality of life on 36 items short form health survey SF-36 scale. Measurements were taken at baselin...
South African Journal of Physiotherapy
Background: People with chronic neck pain show decreased endurance and strength of cervical muscl... more Background: People with chronic neck pain show decreased endurance and strength of cervical muscles with compromised respiratory function. There is little evidence that improvement in breathing function of people with neck pain can help in enhancing cervical muscle strength and pulmonary function. The objective of this our clinical trial was to examine the effects of breathing re-education combined with physiotherapy on endurance and strength of deep neck flexors, and pulmonary function in patients with chronic neck pain.Methods/design: In this double blind randomised clinical trial, 30 patients with chronic neck pain (25–50 years old) were randomly allocated to two groups. Group A, physiotherapy (n = 15), and Group B, breathing re-education (n = 15). The duration of intervention was eight weeks with treatment five days a week. The endurance was measured with the craniocervical flexion test, strength with a handheld dynamometer (Baseline USA) and pulmonary functions with the Spiro l...
African Vision and Eye Health, 2022
Background: Repeatability and validity are important components of precision in any measurement s... more Background: Repeatability and validity are important components of precision in any measurement system.Aim: This study aimed to determine the effect of change in head and neck position and body posture on the repeatability of intraocular pressure (IOP) measurements with PT-100 non-contact tonometer and compare with Goldmann, PT-100 and Schiøtz tonometer readings.Setting: Optometry clinic, Saudi Arabia.Methods: The IOP was measured in one selected eye of 84 healthy participants (mean aged 21.9 ± 2.0 years) using PT-100 in three head and body positions, Goldmann tonometer and Schiøtz on two separate visits, in a randomised fashion. Central corneal thickness (CCT) was measured using an ultrasound pachymeter. The repeatability, agreement and correlations between CCT and IOP differentials were assessed.Results: The IOP measured in three head and body positions with the PT-100 were similar and comparable to Goldmann IOPs in sessions one and two with 74% and 86% of PT-100 measurements with...
International Journal of Occupational Medicine and Environmental Health, 2022
Journal of Musculoskeletal & Neuronal Interactions, 2018
Objective: The present study aimed to compare the effects of quadriceps or calf muscles fatigue o... more Objective: The present study aimed to compare the effects of quadriceps or calf muscles fatigue on static and dynamic standing balance in young healthy adult males. Methods: Forty-five healthy, physically active male adults aged 18-30 years were randomly divided into three groups; Quadriceps muscle fatigue group (n=15), Calf muscles fatigue group (n=15), and a control group (n=15). The Modified Clinical Test of Sensory Interaction on Balance, Unilateral Stance, and Limits of Stability (reaction time and movement velocity) were selected as outcome measures for this study. Results: The results showed a non-significant difference between pretest and posttest balance scores (p>0.05) for quadriceps and calf muscles fatigue on balance. Similarly, there were non-significant differences in posttest balance scores when comparing fatigue effects between the groups (p>0.05). Conclusions: These results suggested that the fatigue of the quadriceps or calf muscles did not influence standing...
Journal of Musculoskeletal & Neuronal Interactions, 2018
Objective: The present study aimed to evaluate the effect of footwear on standing balance in heal... more Objective: The present study aimed to evaluate the effect of footwear on standing balance in healthy young adult males. Methods: Thirty healthy male participants aged 20-30 years were tested for standing balance on the Balance Master on three occasions, including wearing a sandal, standard shoe, or no footwear (barefoot). The tests of postural stability include; “Modified Clinical Test of Sensory Interaction on Balance” (mCTSIB), “Unilateral Stance” (US), and the “Limits of Stability” (LOS). The balance scores (mCTSIB, US, and LOS) was analyzed. Results: There was a significant effect between footwear conditions for mCTIB with eye closed on a firm surface (p=0.002). There was a significant effect between footwear conditions for the US with eye open and closed (p<0.05). There was a significant effect between footwear conditions for LOS reaction time during forward movement (p=0.02). Similarly, there was a significant effect between footwear conditions for LOS reaction time during ...
Investigative Ophthalmology & Visual Science, 2019
Purpose: Intraocular pressure (IOP) is important in the diagnosis and management of glaucoma and ... more Purpose: Intraocular pressure (IOP) is important in the diagnosis and management of glaucoma and remains the most significant, and only modifiable, risk factor for the development and/or progressio ...
Motor Control, 2021
The current study was carried out with the aim of investigating the effect of maximally relaxed l... more The current study was carried out with the aim of investigating the effect of maximally relaxed lying posture on disfluencies in young adults who stutter. A total of 24 participants (17 males, seven females; mean age = 24.9 ± 6.2 years) with developmental stuttering were a part of the study. The participants were asked to perform spontaneous speaking and reading aloud tasks in standard sitting and maximally relaxed lying postures. The severity of stuttering for the studied postures was estimated by using the Stuttering Severity Instrument. The results on the Stuttering Severity Instrument showed that stuttering parameters improved during the maximally relaxed lying posture compared with the standard sitting position. The results are discussed in the light of motor control concepts. It is concluded that the maximally relaxed lying posture can facilitate improvement in stuttering scores during spontaneous speaking as well as reading aloud in young adults who stutter. Reduced stutterin...
International Journal of Environmental Research and Public Health, 2020
Supermarket cashiers face a significant amount of stress, including time constraints, mental pres... more Supermarket cashiers face a significant amount of stress, including time constraints, mental pressure, and physical demands that require repetitive movements. The job description of a supermarket cashier involves work-related risk factors that may lead to musculoskeletal disorder (MSD) symptoms. This study aimed to investigate supermarket cashiers to determine the prevalence of MSD symptoms and their quality of life. Data were collected from a convenience sample of supermarket cashiers working in Saudi Arabia. Information included direct questions on pain in the previous 12 months, demographic data, and health- or occupation-related factors. Moreover, data was collected based on the 36-item short form survey (SF-36), and descriptive statistics were computed. A total of 193 supermarket cashiers participated in this study. The sample included 140 men (72.5%) and 53 women (27.5%), with a mean age of 27.2 ± 6.4 years. The majority of the participants (90%) had MSD symptoms in at least o...
BioMed Research International, 2018
Objective. The present study compared the effects of upright and slouched sitting postures on the... more Objective. The present study compared the effects of upright and slouched sitting postures on the respiratory muscle strength in healthy young males.Methods. A total of 35 adult male subjects aged 18–35 years participated in this study. Respiratory muscle strength was determined by measurement of sniff nasal inspiratory pressure (SNIP) using a MicroRPM device in the upright and slouched sitting positions. The subjects were asked to perform the pulmonary function test including peak expiratory flow (PEF), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio at baseline. Body composition was also determined.Results. There was a significant difference of SNIP score between upright sitting and slouched sitting positions (p=0.04). The mean difference of SNIP score between upright sitting and slouched sitting positions was 8.7 cmH2O. Significant correlations were found between SNIP in upright sitting and FEV1% predicted values [R= .651], SNIP in s...
Brain and Behavior, 2019
BackgroundJaw sensory‐motor system has been shown to affect static balance of the body. It would ... more BackgroundJaw sensory‐motor system has been shown to affect static balance of the body. It would be interesting to know whether it can influence dynamic balance as well. The objective of this study is to examine the influence of different jaw positions on dynamic balance using the Y‐balance test.MethodsEighty healthy male participants aged 20–35 years were invited to participate in this study. Dynamic balance was measured by the Y‐balance test in three directions (anterior, posteromedial, and posterolateral) for each leg separately in three jaw positions: resting jaw (control), open‐jaw, and clenched jaw.ResultsThere were no significant differences in reach distances between the different jaw positions except in the posterolateral direction. In comparison with resting jaw position, reach distance was significantly higher in open‐jaw position for the right leg and in clenched and open‐jaw positions for the left leg in the posterolateral direction.ConclusionsAlthough various studies h...
BioMed Research International, 2018
Background.Assessment of hand grip strength is vital for the evaluation of upper limb impairments... more Background.Assessment of hand grip strength is vital for the evaluation of upper limb impairments and effective exercise prescription. Present study primarily aimed to investigate the effect of head-neck positions on the hand grip strength in healthy young adults. Secondarily, the present study compared hand grip strength between left versus right hand in different head-neck positions.Methods.Healthy young adults (age 19 – 30 year; n = 40) participated in this cross-sectional study. Hand grip strength was assessed in three head-neck positions (neutral, rotation left, and rotation right) using the standard adjustable Jamar hand dynamometer.Results. Hand grip strength in both sides (left and right) was greatest in the head-neck neutral position. Hand grip strength measured in head-neck left rotation position displayed the least strength in both sides. There was no significant difference noted between left and right side hand grip strength measured in head-neck neutral and right rotati...
BioMed Research International, 2019
Objective. The current study aimed to investigate the effects of body position on the level and s... more Objective. The current study aimed to investigate the effects of body position on the level and severity of stuttering in young adults with developmental stuttering. Methods. A total of 24 subjects (male: 17; female: 7; mean age: 24.9 ± 6.2 years) with developmental stuttering participated. The participants were asked to perform oral reading and spontaneous monologue-speaking tasks in different body postures while their speech was recorded. During reading and speaking tasks, the Stuttering Severity Instrument was used to quantify the severity of stuttering. The effects of different body postures on stuttering severity, reading task, and speaking task scores were analyzed. Results. Significant differences in stuttering severity, reading task, and speaking task scores were found for different body postures. Post hoc analyses revealed a significant difference in stuttering severity, reading task, and speaking task scores when subjects were sitting on a chair with no arm support compare...
The Journal of Sports Medicine and Physical Fitness, 2019
BACKGROUND People clench their teeth to activate facial, neck and abdominal muscles when they nee... more BACKGROUND People clench their teeth to activate facial, neck and abdominal muscles when they need to generate heavy muscle force against large resistance like lifting heavy objects, in order to gain possible ergogenic advantage. These are termed as remote voluntary contractions. Aim of this study was to evaluate the effect of voluntary teeth clenching on maximal voluntary contraction of extensors and flexors of the knee, shoulder and elbow joints of the dominant side during slouch and unsupported upright sitting. METHODS One hundred healthy young male adults (mean age 23.3 years) participated in this study. Maximal voluntary contraction was measured using a hand-held dynamometer. RESULTS Jaw clenching caused different ergogenic effect during slouch versus unsupported sitting postures. The data revealed that during unsupported upright sitting, the effect of jaw clenching consistently results in larger maximal voluntary contraction of both extensor and flexor muscles of all the three studied joints. However, during slouch sitting, only the maximal voluntary contraction of extensors of elbow and flexors of knee were larger with clenched teeth position. CONCLUSIONS Jaw clenching can affect the maximal voluntary contraction of limb muscles which is sitting posture dependent. Jaw clenching can consistently facilitate certain muscles of the upper and lower limbs to generate greater force production during upright sitting.
Archives of Oral Biology, 2019
Journal of hand therapy : official journal of the American Society of Hand Therapists, Jan 23, 2017
Cross-sectional and clinical measurement. Assessment of hand function considers an essential part... more Cross-sectional and clinical measurement. Assessment of hand function considers an essential part in clinical practice. To develop normative values of hand grip strength and dexterity function for 6-12-year-old children in Saudi Arabia. Grip strength and dexterity function was measured in 525 children using Grip Track hand dynamometer (JTECH Medical, Midvale, UT, USA) and 9-hole pegboard test respectively. The grip strength and dexterity function was improved as age progressed regardless of gender. Across all age groups, the hand grip strength of boys was significantly higher than girls for dominant hand (31.75 ± 10.33 vs 28.24 ± 9.35; P < .001) and nondominant hand (31.01 ± 10.27 vs 27.27 ± 9.30; P < .001). The girls performed slightly faster than boys for dominant hand (19.70 vs 20.68; P < .05) and nondominant hand (21.79 vs 23.46; P < .05). In general, girls completed a 9-HPT faster than boys in the 2 of 7 age groups: 11 years (9-HPT scores = 2.10 seconds; P < .01)...
Workplace Health & Safety, 2017
Low back pain (LBP) is a common health problem. Professions like physical therapy (PT), involving... more Low back pain (LBP) is a common health problem. Professions like physical therapy (PT), involving frequent lifting, bending, or standing, are at risk for developing LBP. The objective of this study was to determine the prevalence of work-related LBP and factors associated with and consequences of work-related LBP among physical therapists in Riyadh, Saudi Arabia. A self-administered online questionnaire (i.e., demographic data, history of LBP before and after working as a physical therapist, work setting, and effect on daily activities) was sent to 600 members of the Saudi PT association. Data were analyzed using the Pearson chi-square test and Mann-Whitney U test. Eighty-eight percent of potential respondents completed the questionnaire. Of these, 89.65% of the therapists reported LBP after beginning their PT practice, and 35.6% reported LBP at the time of this survey. Gender, PT specialty, and duration of contact with patients were all found to be related to LBP. The prevalence of...
Somatosensory & Motor Research, 2016
Information about head orientation, position, and movement with respect to the trunk relies on th... more Information about head orientation, position, and movement with respect to the trunk relies on the visual, vestibular, extensive muscular, and articular proprioceptive system of the neck. Various factors can affect proprioception since it is the function of afferent integration, and tuning of muscular and articular receptors. Pain, muscle fatigue, and joint position have been shown to affect proprioceptive capacity. Thus, it can be speculated that changes in body posture can alter the neck proprioception. This study was undertaken to investigate the effect of body posture on cervicocephalic kinesthetic sense in healthy subjects. Cervicocephalic kinesthetic sensibility was measured by the kinesthetic sensibility test in healthy young adults while in (a) habitual slouched sitting position with arms hanging by the side (SS), (b) habitual slouched sitting position with arms unloaded (supported) (SS-AS), and (c) upright sitting position with arms hanging by the side (US) during maximum and 30 degree right, left rotations, flexion, and extension. Thirty healthy male adults (mean age 27.83; SD 3.41) volunteered for this study. The least mean error was found for the SS-AS position (0.48; SD 0.24), followed by SS (0.60; SD 0.43) and US (0.96; SD 0.71), respectively. For all test conditions, there was significant difference in mean absolute error while head repositioning from maximum and 30 degree rotation during SS and SS-AS positions (p &amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). In conclusion, body posture can affect the proprioception function of the neck. Supporting the upper extremities in such a way that their weight is unloaded, which leads to reduction in the tension between the neck and shoulder girdle, can improve cervicocephalic kinesthetic sense in both the horizontal and vertical planes. The findings of this study can be implemented in people who have to do repeated arm and neck movements, by using ergonomically effective chairs with proper arm supports. This might help in prevention and treatment of neck pain.
BioMed Research International, 2018
Normal respiration is a very intricate function that comprises mechanical as well as nonmechanica... more Normal respiration is a very intricate function that comprises mechanical as well as nonmechanical components. It is shown to be affected by various factors including age, lifestyle, disease, and change in posture. With the increased use of hand held devices, everyone is prone to poor sitting postures like forward head posture. The purpose of this study was to evaluate the effect of assumed forward head posture and torticollis on the diaphragm muscle strength. A sample of 15 healthy males, aged 18-35 years, was recruited for this study. All subjects performed spirometry to measure the forced expiratory volume in 1 second (FEV1), the forced vital capacity (FVC), and FEV1/FVC ratio. SNIP was measured during upright sitting, induced forward head posture, and torticollis. Subject’s mean age (SD) was 23(6) years. The SNIP score of the subjects during sitting with FHP was lower as compared to that during upright sitting. It decreased significantly during induced right torticollis position...
BioMed Research International
Purpose. Cervical radiculopathy is disorder of cervical spinal nerve root affecting large number ... more Purpose. Cervical radiculopathy is disorder of cervical spinal nerve root affecting large number of population. Previously many studies are conducted to design suitable protocol for management of this disorder, but they lack in quality. The purpose of this study was to compare the effects of neural mobilization and cervical isometrics on health-related quality of life and deep flexors endurance in cervical radiculopathy. Methods. A double-blinded randomized clinical trial was conducted at Mayo Hospital, Lahore, Pakistan. Eighty-eight patients within the age range of 35-50 years were included in the study after taking their consent. In the experimental group ( n = 44 ), median nerve mobilization was applied along with cervical isometric exercises. The control group ( n = 44 ) performed cervical isometric exercises alone. Muscle endurance was measured by craniocervical flexion test and quality of life on 36 items short form health survey SF-36 scale. Measurements were taken at baselin...
South African Journal of Physiotherapy
Background: People with chronic neck pain show decreased endurance and strength of cervical muscl... more Background: People with chronic neck pain show decreased endurance and strength of cervical muscles with compromised respiratory function. There is little evidence that improvement in breathing function of people with neck pain can help in enhancing cervical muscle strength and pulmonary function. The objective of this our clinical trial was to examine the effects of breathing re-education combined with physiotherapy on endurance and strength of deep neck flexors, and pulmonary function in patients with chronic neck pain.Methods/design: In this double blind randomised clinical trial, 30 patients with chronic neck pain (25–50 years old) were randomly allocated to two groups. Group A, physiotherapy (n = 15), and Group B, breathing re-education (n = 15). The duration of intervention was eight weeks with treatment five days a week. The endurance was measured with the craniocervical flexion test, strength with a handheld dynamometer (Baseline USA) and pulmonary functions with the Spiro l...